Legislation and Accreditation

Please click on the links below to quickly access the specific legislation and accreditation sections:

Polycarbonate em.domes have been awarded BBA Certificate No. 09/4691. The key factors assessed in the BBA Certificate are light and solar transmittance, thermal properties, condensation risk, strength and stability, weather tightness, behaviour in relation to fire, safety, ventilation and durability. Download our BBA Certificate here.


This European standard specifies requirements for rooflights made of plastic materials with and without upstands. These rooflights serve the purpose of providing natural daylight to interior of buildings and also ventilating interior spaces by the means of opening devices.
EN 1873 applies to rooflights with square, rectangular or circular shape up to a diameter of 2.5 metres or an opening width of not larger than 3 metres in roof pitches up to 25 degrees. It does not cover rooflights which contribute to the load bearing or stiffness of the roof itself. The standard applies to rooflights with or without upstands where they are provided by a single manufacturer and are purchased in a single purchase.

The exception to the above is where the rooflight is used for smoke and heat ventilation and this is covered by European Standard EN12101-2.  Whitesales Em-Vent Smoke Ventilators fully comply with EN12101-2. For further information please see the Em-Vent page.
This standard does not include calculation with regard to construction, design requirements and installation techniques.

Performance Criteria

The European norm 1873 tests criteria in the following areas:

  • Degree of luminous transmittance.
  • Durability.
  • Watertightness.
  • Upward load.
  • Downward load.
  • Impact resistance in relation to large soft body and small hard body.
  • Reaction to fire.
  • Resistance to fire.
  • External fire performance.
  • Air permeability.
  • Thermal resistance.
  • Airborne sound insulation.


Some or all of the above criteria are tested in accordance with the guidelines set out in EN1873 and the manufacturer has to declare the test results in a Declaration of Performance (DoP).


The products need to be labelled in accordance with CE Directive. This labelling can be on the packaging or the product itself and set out as specified by this European standard. For further information regarding EN1873 please contact Whitesales on 01483 271371 or sales@whitesales.co.uk.
A copy of our DoP can be downloaded here.

Because Smoke Ventilators are Life-saving devices they classify as Level 1 under CE EN120101-2 which stringently regulates the manufacture and sale of these products. The following is an overview of the requirements:

The products need to pass six stringent performance tests.
These include:

  1. Aerodynamic Free Area – the product of Geometric Area and Coefficient of Discharge.
  2. Reliability – 10,000 cycles for normal ventilation, followed by 50-1000 cycles for smoke ventilation.
  3. Opening Under load – within 60 seconds to full fire open position, which for single vents is 140°.
  4. Low temperature – open and close three times at -25°C
  5. Wind load – to establish integrity under suction, and that the vent will open within 60 seconds under this load.
  6. Heat Resistance – at 300°C for 30 minutes.

They need to be tested and certified independently.
All the above tests must be certified by an independent test body in order for manufacturers to produce a genuine Declaration of Performance (DoP) certificate.

The manufacturer and their processes have to have an independent annual audit.
This ensures consistency, with strict monitoring, recording and reporting of criteria known as Factory Production Control (FPC)
The products must have a genuine Declaration of Performance (DoP) Certificate.
The products must be CE certified as a complete unit, not as components.

CE 12101-2 stipulates the labelling of Smoke Vents must show:

  • Name or Trademark of Supplier
  • Type and Model Number
  • Year of Manufacture
  • Power Supply details (e.g. 24VDC)
  • Aerodynamic Free Area (Aₐ)
  • Classes for:
    • Wind load
    • Snow load
    • Low Temperature
    • Reliability
    • Heat Exposure
  • Number & Year of the European Standard EN12101-2:2003

It is very important that when sourcing or specifying a smoke vent that fully compliant products are used. For further information, guidance and assistance see the Em-Vent page or contact Whitesales on 01483 271371 or sales@whitesales.co.uk.
A copy of our DoP can be downloaded here.


Man-safe is a term often used within the construction industry to mean that the product can withstand foot traffic. However man-safe has no recognised definition and ‘Non-Fragile’ does not qualify a product to be used as a thoroughfare.

Whilst glazing and other accessories may be designed to safely resist the impact of a human body falling against it, the willful act of walking on any kind of roof glazing must be forbidden at all times.

The act of walking upon a glazed structure can cause microscopic damage that, in time, may have a detrimental effect upon the impact performance of the system.
Walking upon glazing may encourage a practice that could lead to general disregard for the rating of said glazing, with catastrophic consequences.

BS 6229

BS 6229: 1982, Code of Practice for flat roofs with continuously supported coverings, requires rooflights to incorporate upstands to raise the mat least 150mm above the uppermost roof surface to which the roof covering is bonded or dressed. The designer should ensure that the builder’s curb is at least 150mm high.


Various standards deal with the calculation of U-values of building elements. The conventions provide guidance on the use of the standards, indicating the methods of calculation that are appropriate for different construction types, providing additional information about using the methods and providing data relevant to typical UK constructions. The U-value conventions were originally published by the BRE in 2002 and the 2006 edition is an update which provides additional information and reflects changes in the underlying British Standards. The U-Value calculation methods are also referred to in Approved Documents L1A, L1B, L2A and L2B.

This Approved Document L, which took effect on 1 October 2010, was amended in November 2013 and came into force on 6 April 2014. Click here to read our white paper regarding these changes. It deals with conservation of energy requirements in the Building Regulations (as amended) and is made up of four distinct publications which are summarised below. It should be noted that Approved Documents are guidance publications and there is some provision for trade-off with other building elements – any proposal should be checked with the relevant building control body. U-Values should be calculated in accordance with BRE 2006. The document also covers areas such as Materials and Workmanship including a requirement to demonstrate appropriate use of products with CE marking, British Standards and European Technical Approvals. Whitesales continuous rooflights have undergone stringent and extensive testing and are certified to these standards.

Solar heat gain

Approved Documents L1A and L2A include requirements to limit solar gains through the summer period. The inside of the building can heat up during daylight hours due to the sun. This is termed as solar heat gain. To reduce this effect, solar control glass can be adopted to reflect heat and reduce glare from the sun’s rays. This lessens the burden on air-conditioning systems thus reducing CO2 emissions. In simple form, this may be body tinted glass in blue, green or bronze or more sophisticated, coated clear glass that allows maximum light transmission, but at the same time substantially reduces heat gain.

Optimum rooflight provision

A building’s design will affect the contribution rooflights can make. The optimum area of rooflights will therefore vary for each building. However, research has shown that a rooflight area of 15-20% will contribute to an overall reduction in CO2 emissions inmost buildings. Rooflights are up to three times more effective at supplying daylight than vertical windows. Where artificial lighting is controlled by daylight sensors, installing rooflights can result in a significant reduction in the energy used for lighting. Energy consumed in lighting a building is often greater than that used to heat it. In addition, the SAP and SBEM software programs take account of the contribution made by passive solar gains through rooflights. Solar gains help to offset the increased heat loss of rooflights compared to the insulated main roof.

Air permeability

Air permeability is the physical property used to measure airtightness of the building fabric. It is defined as air leakage rate per hour per square metre of building envelope m3/(h.m2) at the test reference pressure differential across the building envelope of 50 Pascal (50N/m2). The limiting air permeability is the worst allowable air permeability.

This document places the responsibility on the designer to comply with ventilation requirements to new and existing buildings. It states ventilation types including extract, whole building and purge and gives minimum ventilation requirements.

Rooflights are often a useful means of assisting compliance with the requirements especially where no other external ventilation aperture is available.

Further information is available in Building Bulletin 101 – Ventilation of School Buildings.

This document requires that buildings are designed and constructed to provide resistance to sound and reverberation. The aim is to limit noise disturbance by including sufficient acoustic properties and insulation in areas such as internal and external walls, floors and other elements.
Rooflights should perform in accordance with these requirements and the decibel reduction value can be used in calculations for this purpose.

Further information is available in Building Bulletin 93 – Acoustic Design for Schools.

Approved Document B places certain limitations on the use of rooflights, which are dependent on glazing material and site circumstances, such as building size, use of area below rooflights, rooflight size and proportion of total roof area, distance from boundary, etc. The relevant information is set out in Volume 1: Sections 3 and 10; Volume 2: Sections 6, 12 and 13 of Approved Document B, 2006 Edition.

Where applicable, the responsibility for determining that any building component complies with the relevant Regulations rests solely with the customer or specifier.

Whitesales subscribe to NARMLRWASPRANFRC and Constructionline.

Polycarbonate em.domes are manufactured to ISO 9001 standards.

Since 1 July 2013, under the ‘Construction Products Regulation’ (CPR), it has become mandatory for manufacturers of any construction product covered by a ‘harmonised European standard’ (hEN), to apply CE Marking to these products. As a market leading manufacturer and supplier of speciality flat roofing products, Whitesales welcomes this important development; ensuring that all of our products covered by a hEN are appropriately certified.

We have worked exhaustively within our supply chain and manufacturing processes where comprehensive product testing by ‘Notified Bodies’ has been carried out, enabling us to issue the required documentation

Therefore all of our products covered by a hEN (harmonised European standard) are appropriately certified.

View all the relevant hEN numbers that apply to our products.
View the PDF

Dome Rooflight products are covered by EN1873, for more information see below.

Smoke Ventilation products are covered by EN12101-2, for more information see below.